Potentially mobile of heavy metals on the surface sediments in tropical hyper-saline and positive estuaries

ABSTRACT Estuarine sediments represent important pools of trace metals, released from both anthropogenic and natural sources. Fluctuations in the water column physicochemical conditions, on the other hand, may transfer metals from solid to liquid compartment and resulting in contamination of the surrounding environment. The present research was carried out to evaluate the weakly bounded heavy metal levels in tropical hyper-saline and positive estuaries, in order to quantify its potentially availability. The monitoring includes five metals (Cd, Cr, Cu, Pb, Zn) and cover nine estuaries in Rio Grande do Norte state/Brazil, including four hypersaline and five true estuaries. 50 surface sediment samples were collected in each estuary. At the same time, organic matter concentrations were evaluated in order to help explaining possible local variations in heavy metal levels. Organic matter results (0.7% - 7.3%) suggest the positive Potengi estuary as the most critical environmental quality situation. On the other hand, according to heavy metals levels, both Conchas and Potengi estuaries registered the higher concentrations of Cr. The highest concentrations were observed in the hyper-saline estuaries, with the exception of the Zn. The present study revealed that the watershed occupation has significantly influenced the heavy metal concentrations in the estuaries.

Effect of temperature and salinity on larval survival and development of Litopenaeus vannamei / Efecto de temperatura y salinidad sobre la supervivencia y desarrollo larval de Litopenaeus vannamei

ABSTRACT Objective. The combined effect of salinity (25, 30, 35, and 40psu) and temperature (25, 30, and 35oC) was evaluated on survival and development from nauplii V (NV) larvae until postlarvae (PL1) of Litopenaeus vannamei. Materials and methods. Four replicates were applied to each combination of salinity and temperature. The larvae were placed in 12 L beakers a density of 100larvae/L. Salinity was increased dissolving commercial salt without iodine, into marine water, whereas fresh filtered tap water was used to decrease the salinity from seawater. The NV were adapted at 35psu and 30°C during 30 minutes. Thereafter, were transferred at each experimental combination of salinity and temperature. Every 24 h, samples of larvae were obtained to determine in vivo their stage of development and survival. All data were analyzed using a two-way ANOVA. Results. Survival and larval development were significantly (p<0.05) affected by salinity, temperature and interaction of both factors. Maximum ultimate survival to PL1 was obtained at 30°C and 30psu (82.2%) followed by 30 and 35°C at 25psu (71.5 y 71.6%). The highest development at PL1 was found at 30°C and 30psu (6.76). Larval development during experiment was lower at 25°C as compared to 30 and 35°C, regardless of the salinity levels. Conclusions. The most adequate conditions for survival and larval development were obtained between 30-35°C and 25-30psu.

RESUMEN Objetivo. Analizar el efecto combinado de salinidad (25, 30, 35 y 40 ups) y temperatura (25, 30 y 35°C) sobre la supervivencia y el desarrollo de larvas nauplio V (NV) hasta postlarvas (PL1) de Litopenaeus vannamei. Materiales y métodos. Los experimentos se realizaron por cuadriplicado por cada combinación de salinidad y temperatura. Las larvas se mantuvieron en acuarios de 12 L a una densidad de 100larvas/L. La salinidad se incrementó disolviendo sal granulada libre de yodo, a partir de agua de mar, mientras que para alcanzar las salinidades menores se utilizó agua dulce filtrada. Los NV aclimatados a 35ups y 30°C durante 30 minutos fueron transferidos a cada combinación experimental de salinidad y temperatura. Cada 24 h, se obtuvieron muestras de larvas para determinar in vivo su etapa de desarrollo y supervivencia. Los datos fueron analizados por un ANOVA de dos vías. Resultados. La supervivencia y el desarrollo larval fueron significativamente afectadas por la salinidad, temperatura y su interacción (p<0.05). La máxima supervivencia final a PL1 se obtuvo a 30°C y 30ups (82.2%), seguido por 30 y 35°C a 25ups (71.5 y 71.6%). El desarrollo más alto a PL1 fue encontrado a 30°C y 30ups (6.76). El desarrollo larval durante el experimento fue más bajo a 25°C en comparación con 30 y 35°C, independientemente de los niveles de salinidad. Conclusiones. Las condiciones más adecuadas para la supervivencia y desarrollo larval se obtuvieron entre 30-35°C y 25-30ups.

Effect of intraperitoneal CO₂ concentration on postoperative pain after laparoscopic cholecystectomy

PURPOSE: This study set out to identify the association between the intraperitoneal CO₂ concentrations and postoperative pain by dividing the participants into a control group and 2 experimental groups receiving irrigation (1 L and 2 L), and directly measuring their intraperitoneal CO₂ concentrations with a CO₂ gas detector. METHODS: A total of 101 patients, American Society of Anesthesiologists physical status classification I and II patients aged 18–65 years were enrolled in the study. Group 1 did not receive irrigation with normal saline, while groups 2 and 3 were administered irrigation with 1 L and 2 L of normal saline, respectively, after laparoscopic cholecystectomy. Intraperitoneal CO₂ concentrations were measured with a CO₂ gas detector through the port, and postoperative pain was assessed on a visual analogue scale at 6, 12, and 24 hours after surgery. RESULTS: The intraperitoneal CO₂ concentrations were 1,016.0 ± 960.3 ppm in group 1, 524.5 ± 383.2 ppm in group 2, and 362.2 ± 293.6 ppm in group 3, showing significantly lower concentrations in groups 2 and 3. Postoperative pain was significantly lower in group 3 at 6 hours after surgery, and in groups 2 and 3 at 12 hours after the surgery. However, there was no significant difference between the 3 groups in postoperative pain 24 hours after the surgery. CONCLUSION: This study found a causal relationship between the amount of normal saline used for irrigation and the intraperitoneal CO₂ concentrations in that irrigation with normal saline reduces pain on the day of the surgery.

Análisis microbiológicodel pulpo rojo en puertos pesqueros de Campeche, México / Microbiological analysis of red octopus in fishing ports of Campeche, Mexico

Resumen: Objetivo: Estudiar la calidad microbiológica del pulpo rojo dado su importante impacto económico y social en la región sur-sureste de México. Material y métodos: Se tomaron muestras en diversas zonas de captura de la especie y se analizaron con pruebas bioquímicas descritas en las normas oficiales mexicanas. Se identificaron cepas pertenecientes al género Vibrio, Salmonella, coliformes fecales y E. coli O157:H7. Con el empleo del Sistema BAx, se logró la identificación de microorganismos a través de su ADN bacteriano. Los resultados obtenidos en los métodos bioquímicos y moleculares fueron contrastados. Resultados: El método estadístico de Bland-Altman indicó que ambas técnicas pueden usarse indistintamente. La prueba de McNemar demostró que ambos métodos cuentan con la misma eficacia para la identificación de patógenos (valor X2=0.5 ρ=0.4795). Conclusión: La calidad microbiológica del pulpo en la región sur-sureste de México es deficiente debido a la presencia de flora bacteriana patógena que podría representar un riesgo epidemiológico. Los índices establecidos por las normas sugieren la necesidad de aplicar técnicas de identificación eficaces y rápidas como el Sistema BAx. Este método alternativo de análisis puede coadyuvar a la implementación de estrategias efectivas que permitan cumplir con especificaciones mínimas sanitarias durante el procesamiento de los productos pesqueros, y así elevar los sistemas de control para disminuir los riesgos de brotes epidemiológicos en la región.

Abstract: Objective: In this work we studied the microbiological quality of the red octopus given its important economic and social impact on the region South-Southeast of Mexico. Materials and methods: Samples were taken in different areas of capture of the species and analyzed with biochemical tests described in the Mexican official standards, identifying strains belonging to the genus Vibrio, Salmonella and faecal coliforms, and E. coli O157: H7. We used the BAx System for the identification of microorganisms through their bacterial DNA. The results obtained in biochemical and molecular methods were confirmed. Results: Bland-Altman statistical method pointed out that both techniques can be used interchangeably. McNemar test showed that both methods have the same efficacy for the identification of pathogens (value X2=0.5 ρ=0.4795). Conclusion: The microbiological quality of the octopus in the South-Southeast region of Mexico is deficient due to the presence of pathogenic intestinal flora that might represent an epidemiological risk. The indexes established by the regulations suggest the need to apply effective and rapid identification technologies, such as the BAx System.This alternative method of analysis can contribute to the implementation of effective strategies that allow compliance with the minimal sanitary specifications during the processing of fishing products, thus strengthening the control systems to decrease the risks of epidemiological outbreaks in the region.

Prevention of contrast induced nephropathy with sodium bicarbonate (the PROMEC study) / Prevenção de nefropatia por contraste com bicarbonato de sódio (o estudo PROMEC)

Introduction: Contrast-induced nephropathy is a common complication of radiographic procedures. Different measures have been used to avoid this damage, but the evidence is controversial. New investigations are required to clarify it. We investigated the efficacy and safety of sodium bicarbonate solution compared with sodium chloride solution to prevent contrast induced nephropathy in patients with or at risk of renal dysfunction. Methods: A prospective, single-center, randomized clinical trial conducted from May 1, 2007 to February 8, 2008. Inpatients in a tertiary center, scheduled to undergo a procedure with the nonionic radiographic contrast agent iohexol. There were 220 patients with serum creatinine levels of at least 1.2 mg/dL (106.1 µmol/L) and/or type 2 diabetics, who were randomized to receive an infusion of sodium chloride (n = 113) or sodium bicarbonate (n = 107) before and after contrast dye administration. The intervention were "A" group received 1 ml/kg/hour of normal saline solution, starting 12 hours before and continuing 12 hours after iohexol contrast. "B" group received 3 ml/kg of sodium bicarbonate solution (150 mEq/L) one hour prior to procedure and then drip rate was decreased to 1 ml/kg/hour until 6 hours post procedure. Our main outcome measure was change in serum creatinine. Results: The mean creatinine value after the procedure was 1.26 mg/dL in the saline group and 1.22 mg/dL in the bicarbonate group (mean difference: 0.036; CI 95%: -0.16 to 0.23, p = 0.865). The diagnosis of contrast-induced nephropathy, defined by increase in serum creatinine on 25% or more within 2 days after administration of radiographic contrast, was done in twelve patients (12%) in the bicarbonate group and eighth patients (7.1%) in the saline group (RR: 1.68, CI 95%: 0.72 to 3.94). Conclusion: Our investigation showed that there were no differences between normal saline solution (extended infusion) vs. bicarbonate solution ...

Introdução: A nefropatia induzida por contraste é uma complicação comum de procedimentos radiográficos. Medidas diferentes têm sido utilizadas para evitar estes problemas, mas a evidência é controversa. Novos estudos são necessários para esclarecer isso. Investigamos tanto a eficácia quanto a segurança de uma solução de bicarbonato de sódio em comparação com a solução de cloreto de sódio para evitar nefropatia por contraste em pacientes com ou em risco de desenvolver disfunção renal. Métodos: Estudo prospectivo, randomizado clínico, conduzido em um único centro, entre 01 de maio de 2007 e 8 de fevereiro de 2008. Os pacientes internados em um centro terciário, agendados para passar por um procedimento radiográfico com uso de contraste não iônico., Havia 220 pacientes com níveis de creatinina sérica de pelo menos 1,2 mg/dL (106,1 mmol/L) e/ou diabéticos do tipo 2, que foram escolhidos aleatoriamente para receber uma infusão de cloreto de sódio (n = 113) ou bicarbonato de sódio (n = 107) antes e após a administração do meio de contraste. A intervenção foi: grupo "A" recebeu 1 ml/kg/hora de solução salina normal, começando 12 horas antes e continuando por 12 horas após o uso do contraste iohexol. Os pacientes do grupo "B" receberam 3 ml/kg de uma solução de bicarbonato de sódio (150 mEq/L), 1 hora antes do procedimento e, em seguida, o gotejamento foi reduzido a 1 ml/kg/hora por até 6 horas após o procedimento. Nosso principal indicador de desfecho foi a alteração na creatinina sérica. Resultados: O valor médio da creatinina após o procedimento foi de 1,26 mg/dL no grupo que recebeu a solução salina e 1,22 mg/dL no grupo do bicarbonato (diferença média: ...

Supervivencia de postlarvas de camarón blanco Litopenaeus vannamei a diferentes salinidades y temperaturas / Survival of white shrimp Litopenaeus vannamei poslarvae at different salinities and temperatures

Objetivo. Analizar el efecto combinado de salinidad (5, 15, 25, 35 y 45ups) y temperatura (15, 20, 25, 30 y 35°C) sobre la supervivencia y frecuencia de mudas en postlarvas (PL12) de Litopenaeus vannamei. Materiales y métodos. Los experimentos se realizaron por cuadriplicado por cada combinación de salinidad y temperatura. Las postlarvas se mantuvieron en acuarios de 3 L a una densidad de 100PL/l. La salinidad se incrementó disolviendo sal granulada libre de yodo, a partir de agua de mar, mientras que para alcanzar las salinidades menores se utilizó agua dulce filtrada. Las postlarvas aclimatadas a 35ups y 28°C (condición inicial) fueron sometidas abruptamente a las salinidades y temperaturas experimentales por 30 minutos. Después, se filtraron y se colocaron nuevamente en su condición inicial para su recuperación. Transcurridos 30 minutos, se contaron las postlarvas vivas y las mudas. Los datos fueron analizados por un ANOVA de dos vías. Resultados. Se determinó que la supervivencia y frecuencia de mudas fueron significativamente afectadas por la salinidad, temperatura y su interacción (p<0.05). Se obtuvo una supervivencia máxima y mínima de 99.8 y 94.4%. Los porcentajes de supervivencia y frecuencias de mudas disminuyeron a una baja salinidad en combinación a bajas y altas temperaturas, y aumentaron independientemente de la salinidad y temperatura, a excepción de 5ups con 15, 30 y 35°C. La mortalidad máxima de postlarvas fue de 5.6% (5ups y 30°C). Conclusiones. Se determinó que a temperaturas de 20 y 25°C en combinación a las salinidades utilizadas, fueron las mejores condiciones de supervivencia y de resistencia de las postlarvas ante dichas condiciones hidrológicas.

Objective. The combined effect of salinity (5, 15, 25, 35, and 45psu) and temperature (15, 20, 25, 30, and 35°C) was evaluated on survival and molt frequency in Litopenaeus vannamei postlarvae (PL12). Materials and methods. Four repetitions were applied to each combination of salinity and temperature. The PL were placed in 3 L beakers at a density of 100PL/l. Salinity was increased by dissolving commercial salt without iodine, into marine water, whereas fresh filtered tap water was used to decrease the salinity from seawater. The PL were adapted at 35psu and 28°C (initial conditions) during 30 minutes. Thereafter, they were transferred to each experimental combination of salinity and temperature by 30 minutes. Following this procedure, the PL were filtered and returned to their initial acclimatization conditions. After 30 minutes of recuperation, the live PL and molts were counted. All data were analyzed using a two-way ANOVA. Results. Survival and molt frequency were significantly (p<0.05) affected by salinity, temperature and the interaction of both factors. The maximum and minimum survival rates of 99.8 and 94.4% were obtained. Survival and molt frequency rates were significantly (p<0.05) affected by salinity, temperature and the interaction of both factors. Survival and molt frequency percentage rates decreased at lower salinity in combination with lowest and highest temperatures, and significantly increased, independently from salinity and temperature conditions, with exception of 5psu at 15, 30 and 35°C. The highest mortality rate (5.6%) was obtained at 5psu and 30°C. Conclusions. It was determined that survival of postlarvae was higher at temperatures of 20 and 25°C given salinity combination, which are considered the best conditions for survival and resistance.